Trailer



C G. IRWIN May 1, 1928.

TRAILER Filed Feb. 1, 1927 2 Sheets-Sheet l May 1, 1928. 1,668,079 9. G.IRWIN 1 TRAILER Filed Feb. 1. 1927 2 Sheets-Sheet 2 Patented May 1,1928.

PATENT o FFICE.

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TRAILER.

1 Application "filed February My invention relates to trailers of motortrucks and especially 1 to means for coupling the trailer to its leader.i i

All the motortruck trailers in present use, that have come to .myknowledge, have the common disadvantage of notproperly following in thetrack of itsleader. That is, when making a turn, the trailer has atendency to continue straight ahead until brought around to thedirection of the leader .with a jerk, which often swings it toofariinthe opposite direction, so that it is broughtback by another jerk,and this "turning process consists ofa number'of vigorous jerks or .awhiplping actionwhich resultsin subjecting t e draw barand coupling,andfin fact the frame of both leader and trailerto sudden and unduestrains, with the consequent rapid wear on the various parts, requiringfrequent costly repairs 1 and replacements, which are alsoexpensive inlost time while the equipment is outof service.

This same whipping action develops more or less even duringa straightpull, and especially if the road 'is rough, in whichcase if either theleader or the trailer strikes a deep rut, the sudden strain resulting isso severe as to be liable to break the couplingsgor some related part,andthe leader and its train may be stranded on theroad with attendantdelayen-d annoyance.

My invention deals especiallywith four wheeled trailers, but maybeequally successfully applied to any other type of trailer.

The principal object of my invention is to provide a coupling means forattaching a trailer to its leader which will eliminate the said swayingand jerking of the trailer as it follows along a straight road; and atthe same time so to adaptmy coupling that the wheels of a trailer willfollow in the path of the wheels of the leader while turning, withoutexcessive wear. and resistance to the draw bar. I

A still further object is to provide a coupling simple in construction,economical of manufacture, and adapted to meet all the conditions of theroad.

These objects and the details of construction will hereinafter beexplained and described with reference to the accompanying drawings.

I attain my objects in a vehicle trailer, in combination with thevehicle frame and the steering wheel platform, the said platform 1, 027.Serial no. 10am. I

provided with-an A-frame extension, and a pivoted guidesblcckcarried bythe frontend of said extension. I providea spr ng restrained couplingmember carried .by the front end of the saidplatform and a drawbarhaving its inner end counected to said coupling member, and its frontend slidably bearing in said pivotedguide-block.

In the drawings:

Fig. lgshows a side elevation of :a four- .iwheeled trailer coupled toits leader,

Fig. 2 shows a larger scaled side elevation of the forward part ofatrailerand the'details of my coupling;

Fig. 3 shows a top plan view of the for ward portion of a trailerandfurther details of the coupling; 1

Fig. 4 shows a plan viewsimilartoFig- 3 except the front wheels areshownturned at an angle tothe frame oftthe trailer and the changedposition of the draw bai with rela tion to the 'A frame, which isconnected to the front wheels;

Fig. 5 shows the details ofconstruction of the means for attaching thedrawbarito the trailer frame, and to the apex I of the A frame; and iFig. 6 shows another method of aflixing the draw bar to the frame of thetrailer.

The frame a of the four wheeled trailer is ,ri idly mounted on .springsover the rear wieels b and is mounted over the front wheels for limitedhorizontal rotation on a platform a which 'is rigidly mounted on springsover the front wheels 03.

An A frame e is hinged for vertical movement to the platform 0 as at fand f, and is provided at its apex with a guide 9 through which a drawbar h slides freely. The raw bar h is provided at each end with eyes jand la and the eye j is loosely attached to an eye bolt i which extendsthrough the front transverse portion of the frame a, and is providedwith a heavy compression coil s ring I which bears against the inside oft e frame a and a washer m, which is held in place on the end of the e ebolt b a suitable nut. The eye is on t e draw ar is fastened by anysuitable means to the leader as shown in Fig. 1.

The guide 9 is pivotally secured to the apex of the A frame b a bolt gover which a spring 0 is mounte thus providing limited flexibility tovertical strain.

Referring now to Fig. 3', the relative position of the front wheels andthe frame of the trailer is shown during a straight pull, when thepulling force is coincident with the plane of the draw bar, and Fig. 4shows the relative position when the trailer is following its leader oneturn, and the draw bar it by means of its free movement in the uide ghas changed the direction of the rent wheels, but at theesame time heldthem,

- the leader or those smaller changes due to the roughness of the road,and at the same time by means of the A frame connected to the platform aand the draw bar in which it is journaled prevents free lateralmovements or whipping either on a: turn or during a straight pul Undercertain conditions the spring 1 provided on the eye bolt i is notnecessary and as shown in Fig. 6 an eye bolt z" may then be fixedrigidly to the frame a of the trailer by a nut i but otherwise my devicewill be the'same and will function in exactly the same manner. 1

I claim:

1. In a vehicle trailer, incombination with the vehicle frame and thesteering wheel platform, the said platform provided with an A-frameextension, a pivoted guide-block carried by the front end ofsaidextension and a draw-bar having its inner end connected to the front endof the vehicle frame and its front end slidably bearing in said pivotedguide-block.

2. In a vehicle trailer; in combination with the vehicle frame and thesteering wheel platform, the latter provided with an extension, a springseated pivoted uide-block carried by the front end of sai extension anda draw-bar having its inner end con nected to the front end of thevehicle frame and its front end slidably bearing in said pivotedguide-block.

3. In a vehicle trailer, in combination with the vehicle frame and". thesteering wheel platform, the latter providedv with an extension, aspring seated, ivoted guide-block carried by the front end of saidextension, a spring restrained coupling member carried by the frontendof the said platform and a draw-bar having its inner end connected tosaid cou ling member, and its front end slidablyearing in said pivotedguide-block.

4. In a vehicle trailer, in combination with the vehicle frame and thesteering wheel platform, the said platform. provided with an A-frameextension, a spring seated pivoted guide-block carried by the front endof said extension and a draw-bar liavin its inner end connected to thefront end 0 the vehicle frame and its front end slidably bearing in saidpivoted guide-block,

5. In a vehicle trailer, in combination with the vehicle frame and thesteering wheel platform, the said platform provided with an A-frameextension, a spring seated pivoted guide-block carried by the front endof said extension, a spring restrained cou ling member carried by thefront end 0 the said platform and a draw-bar having its inner endconnected to said coupling mem her, and its front end slidably bearingin said pivoted guide-block.

CHARLES G. IRWIN.

